Abstract

A waveguide fabricated on top of a bottom-waveguided gold-nanowire grating device excites additional resonance modes through interaction between the two waveguides, which overlaps the “intrinsic” resonance mode of the bottom waveguide. Thus, the TE polarized (parallel to the goldnanowires)waveguide mode and TM polarized (perpendicular to the nanowires) coupled mode between the waveguide mode and the particle plasmon resonance of the goldnanowires are enhanced significantly in a tunable spectral band. The top waveguide also extends considerably the spectral tuning range of this optical filter device.

Received 25 June 2008Accepted 15 August 2008Published online 05 September 2008

Acknowledgments:

The authors acknowledge the financial support by the High-tech Research and Development Program of China (2007AA03Z306), the Natural Science Foundation of China (10774011), and the Beijing Municipal Education Commission (KZ200810005004), as well as the microscopic measurements by the Institute of Microstructure and Property of Advanced Materials of the Beijing University of Technology (BJUT-GTS-200704).